The main objective of this study is to investigate the physical, chemical and biological effects of compost made from food waste and unshredded dry leaves and to evaluate the performance of food waste compost on the growth of dwarf crape jasmine (dwarf Tabernaemontana divaricate). Food waste and dry leaves with a ratio of 3:1 have been added to the passive aeration-static bioreactor. The composting was carried out for 40 days. The physical, chemical, biological and morphological changes that occurred during the composting process were identified and evaluated. The plants were grown in media containing nine different proportions of compost and the plant growth was measured after 150 days. The results show that a maximum composting temperature of 47.8 °C and a decrease in the moisture content were achieved. The pH value increased while the electrical conductivity decreased during the composting process. The TOC decreased from 56% to 42%. The nutrient value of the composts was all within the recommended range. Among the treatments, the 5%-20% compost mixture shows the greatest growth development. Results in this study indicate that food waste composting with high EC compost value can be used to promote dwarf crape jasmine growth, provided that the mixture contains low compost dosage.

Composting is a controlled biological process that converts organic matter into soil conditioner and kinetic modelling is necessary to design the composting system. The aims of this study are to determine the optimum compost mixture and turning frequency for food waste and dry leaves composting, as well as to evaluate an elemental kinetic model based on volatile solids (VS). The elemental kinetics of the process were determined using pseudo zero-, first-, second- and n-order equations. Three different feedstock mixtures were used, namely 40% FW (Mix A), 60% FW (Mix B) and 80% FW (Mix C). Four sets of experiments (TF for every 0, 1, 3, and 5 days) were conducted to investigate the turning frequency (TF). The composting process was carried out in a compost bottle for 40 days. Based on organic matter loss, Mix B and C had the highest OM loss, indicating an acceptable initial compost mixture. The turning frequency of every three days resulted in the highest organic matter loss. Kinetic analysis was performed using coefficient correlation (R2), root mean square error (RMSE) and modelling efficiency (EF). Application of the second-order model resulted in good responses for compost mixture Mix B and C. Meanwhile, the n-order model successfully estimated the VS changes for the 3-days TF.

No abstract

No abstract